[vcpkg_find_acquire_program] add gettext's msgmerge program

[wrobelda]

Describe the pull request

Adds support for gettext's msgmerge program

• What does your PR fix? Fixes [gettext] msgfmt (and other gettext bin tools) missing on macOS & Windows #13518

• Which triplets are supported/not supported? Have you updated the CI baseline?
  Downloads tool for Windows, adds hints for macOS and Linux.

• Does your PR follow the maintainer guide?

Yes. Note that I intentionally did not replace the program name and version in the URL with variables because the upstream zip also includes the iconv binaries, so to not mislead a future updater that updating a version variable is enough.

[Neumann-A]

theoretically #11776 can built all of gettext but that is currently blocked by #12936

[wrobelda]

/azp run

[azure-pipelines]

Commenter does not have sufficient privileges for PR 13532 in repo microsoft/vcpkg

[wrobelda]

@JackBoosY looks like osx build has stalled and was killed, hence the failure. Mind triggering the build again?

[wrobelda]

On a second thought, while this allows ports to use the msmerge, it will also require a modification of the personal project's CMakeLists, should it also need msgmerge for its own purposes.

Moreover, brew install gettext or apt install gettext is necessary for macOS\Linux hosts, including your CI nodes, which can potentially cause conflicts with the gettext library installed using a portfile as a dependency.

I suppose you can close it for now and we should wait until #11776 gets merged.

[wrobelda]

theoretically #11776 can built all of gettext but that is currently blocked by #12936

@Neumann-A When you say "theoretically", does you mean that it does that already but e.g. it hasn't been tested, or does it require additional work?

[JackBoosY]

Fine, please ping me if this issue needs to be considered.

[wrobelda]

@JackBoosY unfortunately, the vcpkg's native gettext implementation did not eventually arrive with the generator tools included. I can't find it now, but I saw @Neumann-A confirming it somewhere in #11776 or the related PRs.

From the conversation I had with @ras0219 on Slack, it seems that the current approach remains the same as before, i.e. to use the msys2 gettext package on Windows in case tools are needed:

I believe right now what generally happens is that on Linux/OSX we expect the generator tools from your system and on Windows we get the generator tools from msys2.

Therefore I believe that this PR adding msgmerge to vcpkg_find_acquire_program takes things a step forward. With that change in place, one can use the vcpkg gettext as a dependency and just add these:

vcpkg_find_acquire_program(GETTEXT_MSGMERGE)
get_filename_component(GETTEXT_MSGMERGE_EXE_PATH ${GETTEXT_MSGMERGE} DIRECTORY)
vcpkg_add_to_path(${GETTEXT_MSGMERGE_EXE_PATH})

One thing I also experimented with and tested was adding those to the msys2 default environment. Additionally, all generator tools should be discussed to be added, not just msgmerge – although this only addresses the latter.

I would appreciate your input and hopefully the correct approach to gettext usage can find its way into official Maintainer Guidelines.

[Neumann-A]

cd0c444 adds feature tools to gettext. I don't know when I have time to move it out into a separate PR.
Building all the tools requires some time and also another patch to make autopoint und gettextsize relocatable. (Both are shellscripts hardcoding an absolute prefix.)

[JackBoosY]

See #16612